Background Information
A cathode-ray tube, such as is used in a television set, a computer display, or other monitor, includes a screen which gathers static electricity when the cathode-ray tube is functioning. Typically, the tube is manufactured with a film that overlays the screen. The film consists of a number of different layers, each serving a different respective purpose. One or more of the layers is usually constructed of a conductive material such as indium tin oxide (ITO) which serves to conduct the build up of static electricity to an edge of the screen. A metal tape is attached to the film at the edge of the screen and serves to conduct the static electricity further to a ground, such as to a metal implosion protection band of the cathode-ray tube. A good electrical and mechanical connection is required between the metal tape and the film.
An existing method of attaching the metal tape to the film is by perforating the metal tape and engaging the perforations with complementary solder patches which are applied to the film. One of the layers of the film is usually made of a plastics material such as polyethylene teraphthalate (PET) which melts at a temperature below the temperatures of conventional flux soldering techniques. The solder patches therefore have to be applied by means of a special low temperature flux-less ultrasonic soldering iron.
Not only is the tape expensive to manufacture accurately, but the existing process requires a high level of skill and is labor intensive both from the point of view of applying the solder patches and attaching the metal tape to the film.